FreePN is fairly new on the scene and I have only been using their network on my Ubuntu notebook for a few months. That said, it is certainly the privacy-centered project that has me most excited to see where it goes. All of their code is open-source, which means one could verify that they aren't tracking what sites you visit, although I am not sure it has received enough attention for security experts to perform thorough audits. No registration is required to use the service and it is built on an encrypted, peer-to-peer, decentralized network, arguably the gold standard architecture for privacy. As the name suggests, it is completely free to use with no data caps, bandwidth limits, speed throttling, or restricted access. The speed is good, but the GUI is still in early development and it isn't the most user-friendly option out there yet. I am hopeful that this project will get more traction and we will see additional features along with a more polished UI/UX -- I think FreePN has the potential to completely disrupt the VPN market and only time will tell if it can do so successfully.